could this be used on webOS TV for h/w decoding (Mali G-52)?

[cscd98]

Kernel is Linux LGwebOSTV 5.4.268-320 #1 SMP PREEMPT Mon Jun 17 01:25:25 UTC 2024 aarch64 GNU/Linux

Unfortunately only video20 is allowed without root. I would need to root my TV to see what /dev/video0 is. However, it would not be a good solution for end users to require root anyway (is root required for active use, or only for v4l2-ctl)

ls -la /dev/video*

lrwxr-xr-x    1 root     root            11 May 10 12:46 /dev/video -> /dev/video0
crw-rw----    1 root     video      81,  15 May 10 12:46 /dev/video20

./v4l2-ctl --device=/dev/video20 --all

Driver Info:
	Driver name      : v4l2_vdec
	Card type        : v4l2_vdec
	Bus info         : 
	Driver version   : 5.4.255
	Capabilities     : 0x80200002
		Video Output
		Extended Pix Format
		Device Capabilities
	Device Caps      : 0x00200002
		Video Output
		Extended Pix Format
Priority: 2
Format Video Output:
	Width/Height      : 0/0
	Pixel Format      : ''
	Field             : Any
	Bytes per Line    : 0
	Size Image        : 0
	Colorspace        : Default
	Transfer Function : Default (maps to Rec. 709)
	YCbCr/HSV Encoding: Default (maps to ITU-R 601)
	Quantization      : Default (maps to Full Range)
	Flags             : 

~/temp $ ./v4l2-ctl -d 20 --list-formats-out

ioctl: VIDIOC_ENUM_FMT
	Type: Video Output

~/temp $ ./v4l2-ctl -d 20 --list-formats

ioctl: VIDIOC_ENUM_FMT
	Type: Video Capture

[mxsrc]

As far as I can tell, the v4l2-m2m API was introduced only in Linux 5.11 and has seen regular changes since then. So a more recent kernel would be required, if that's a possibility on your device, it might become feasible. The SoC in principle does have a driver with the appropriate interface though.

[cscd98]

Unfortunately its not possible to update the kernel, at least for end users of LG TVs.